The Greek debt crisis dominated headlines in 2015, amid concerns about broader financial contagion. Former Greek Finance Minister Yanis Varoufakis, who pushed against austerity placed on his country as a “debt bailout” condition, has unique experience and perspectives when it comes to debt.

“America doesn’t have a debt problem,” he told Yahoo Finance. “What you have a problem with is investment. Investment in fixed capital, in productive capacities, is very low compared to your savings and the amount of liquidity sloshing around the financial sector. You need to boost investment in things humanity needs.”

His book, “Adults in the Room,” which was just published in the US on Oct 3, highlights the lack of power even for those in power.

For US President Donald Trump, he has direct advice: Don’t antagonize China.

“[Do] not antagonize China because you’re playing with fire as you’re boosting the federal budget deficit,” he said. “Playing with fire on the other side of the Pacific with your major creditors at the time when they are keeping the global economy going…is a very silly policy.”

Former Greek Finance Minister Yanis Varoufakis sits down with Yahoo Finance’s Nicole Sinclair to talk about the broader implications of the Greek debt crisis and his book “Adults in the Room”

Varoufakis added, meanwhile, that ‘fake news’ has been a long-lasting problem for liberals and conservatives alike.

“The liberal establishment is complaining about fake news coming from the alt right…They have good cause to complain about that. But it was the very same liberal establishment that only two years ago were practicing the same fake news strategy against people like myself,” he said. “I would go into meetings with people like Mario Draghi of the European Central Bank, Jack Lew in Washington DC, Christine Lagarde at the IMF… and the systemic liberal press would misreport and distort utterly and completely what I was saying in those meetings…So it’s a bit rich coming from them when they’re now complaining for the fact that Donald Trump has upended them using their own techniques against them.”

Varoufakis added his most significant conversations in 2015 as he sought to navigate the crisis were with Wolfgang Schauble, the German finance minister, because they reflected the powerlessness of power.

“He is the most powerful finance minister of Europe and maybe of the world…agreeing with me that what was being done to my country was detrimental to the interest of my country but also to Europe,” he said. “And the two of us finding ourselves in a situation where both of us were powerless…Power is propagated without the powerful having it,” he said.